WITH decontrol of oil prices and the proposed acceleration of natural gas decontrol, the Reagan Administration has reaffirmed the U.S. commitment to free markets for energy. No longer will federal policy try to shelter consumers from the costs of higher world energy prices. Even though energy prices are relatively stable today, another round of sharp oil price increases seems likely at some point in the next decade, and this time U.S. energy prices will be permitted to rise immediately as free markets dictate.